Vibration devices may be used for various electronic equipments such as a mobile communication terminal, a speaker, and a video game console. Representatively, such a vibration device performs a vibration function for informing signal arrival and a signal input in the mobile communication terminal.
The vibration device transmits vibration of a weight flexibly supported by a spring to the outside to generate vibration at the electronic equipments.
A vibration quantity of the vibration device is in proportion to a square of a resonant frequency. Thus, deviations occur in an elastic coefficient of the spring and size of the weight due to a deviation generated in a manufacturing process of the weight or the spring to disperse the resonant frequency.